GPT-2: (Hardware) requirements for fine-tuning the 774M model
Possibly a bit late to the answer, but I doubt you'd be able to run GPT-2 774M in FP32 on 2070 Super which has 8GB VRAM. I know it's not an exact comparison, but fine-tuning BERT Large (345M) in FP32 easily takes more than 10GB of VRAM. You might be able to run GPT-2 774M if you run it in FP16.
Alternatively, you can use Google Collab TPUs which provide at 11GB+ VRAM. Here's a good source listing a few posts about fine tuning GTP-2 1.5B on Google Collab TPUs: https://news.ycombinator.com/item?id=21456025
And here's the notebook itself demonstrating the process: https://colab.research.google.com/drive/1BXry0kcm869-RVHHiY6NZmY9uBzbkf1Q#scrollTo=lP1InuxJTD6a